A missense mutation in the SEDL gene results in delayed onset of X linked spondyloepiphyseal dysplasia in a large pedigree

Editor—Spondyloepiphyseal dysplasia (SED) is a rare osteochondroplasia, characterised by disproportionate short stature with a short neck and trunk and barrel chest. The pelvis tends to be narrow and deep, the femoral neck short, and the femoral head flattened. Mild to moderate epiphyseal dysplasia of the large joints may also be seen. The latter may lead to premature secondary osteoarthritis with significant morbidity.1 SED may occur sporadically; however, in many cases the family history indicates an inherited condition. In some of these pedigrees, the inheritance pattern seems autosomal dominant, while in others it is consistent with autosomal recessive or X linked recessive.2 Recently, mutations in the gene designated SEDL , located on Xp22, were identified as the cause of X linked spondyloephiphyseal dysplasia tarda in three families.3 We have previously described a large kindred of British descent spanning four generations affected by SED.1 Briefly, 14 males between the ages of 10 and 77 years were affected, with early adolescence development of progressive decline in growth rate accompanied by short stature, short trunk, and barrel chest. Although some of them had to limit their activities because of hip or back limitation of movement or pain, many continued with normal activity and were …